During the developing CRC, the Data Management and Biostatistics (DMB) Core successfully fulfilled its mission by creating an integrated CRC Database, establishing an effective data management system, providing consultation and training in database development, study design, and biostatistical consultation, and advancing statistical methodology. Through this mission, the DMB Core served the CRC by enhancing the effectiveness, efficiency, and validity of scientific investigation into geriatric affective disorders. The DMB Core will build on these achievements by performing ten specific functions: Research Coordination: provide technical assistance to the Clinical Core of research subjects by assisting database design and by entering data on CRC subjects; Data Acquisition/Quality Control: ensure that the DMB Core provides accurate data entry procedures and valid methods of error detection and correction procedures; Documentation: provide procedures and documentation on all aspects of DMB Core activities, including generation of periodic reports on the state of data collection, documentation on editing errors in the database, descriptions of the coding system and variable names in the database, and tabulation of data sets used in analysis; Protection: ensure patients' confidentiality and security for data as well as provide reliable procedures for data backup and archiving; Data Management: provide an accurate and valid CRC database on which analyses are performed, and a centrally accessible database for all CRC affiliated investigators; Biostatistical Consultation/Data Analysis: provide biostatistical consultation and data analysis so that CRC affiliated research activities become cost effective, thereby increasing quality and productivity; Statistical Research and Development: ensure that statistical methods used by the DMB Core are up- to-date with the most current methods available; Software Research and Development: provide consultation on the latest software packages; Training: offer regular training programs in statistics, data collection, data processing, and programming to all CRC investigators and research associates to advance their skills in new statistical methods for analyzing psychiatric data; Executive Functions: ensure the effectiveness of DMB Core activities: The Advisory Committee and Subcommittee for the Data Management and Methodology will review the data flow from the various CRC components, the performance of the data management system, requests for data analysis, data integrity and requests for data access.